Deaerating system for water or steam condensate



5, 1952 Q A. KIRKPATRICK ET AL 2,605,856

DEAERATING SYSTEM FOR WATER OR STEAM CONDENSATE Filed July 2, 1947 61.earn 23 766 for BY Harry H. MMeen Patented Aug. 5, 1952 DEAERATINGSYSTEM FOR WATER on 'STEAM CONDENSATE Alton Kirkpatrick, Boston, Mass,and Harry H.

McMeen,Harvey, Ill., assignors, by mesne as- 'signments, to the UnitedStates of America as v, Energy Commission represented by the UnitedStates Atomic f Application July 2, 1947, Serial No, 758,542

Our invention relates to cooling systems and more particularly to thetype of cooling system employing deaerating equipment for the removal ofgases and/or otherimpurities ingaseous form from the liquid orcirculating medium of the system.

In the operation of production equipment used in connection withjtheelectromagnetic process of particle separation athigh potentials andunder conditions wherev large power consumption is involved, and where apart of the power is converted into heat energy, it becomes necessary tocirculate a cooling medium, such as water, through the walls and heatedpartsof the apparatus to prevent overheating 'of or injury tosuch-parts. Due to the high operating potentials of, this equipment andto the fact that the lead line for the cooling liquid is ordinarilymaintained at or near ground potential, it is customary to employ lapcoils oiinsulated material, such as porcelain, to join the lead lines tothe high potential elements of the equipment. Under these circumstancesit is necessary that the cooling medium also be a good insulator with aminimum ionization and low conductivityto prevent leakage between'the'elements and the lead lines through this, liquid. To accomplish thisresult, the liquid or medium is deaerated to remove air and such gasesas CO?, (carbon dioxide) which react with the medium when water 'isused, to produce carbonic acid, the reaction being:

undesirable gases to reduce corrosion has been known to the prior art.Examples of such systems may be found in the patents to Elliott,1,457,153; McDermet, 1,742,998; and Gibson, 1,969,888. These structures,however, fall to make provision for a storage reservoir and a deaeratingchamber, both under vacuum to obviate the possibility of gases enteringor being absorbed by the liquid. Additionally, they fail to tak intoaccount the necessity for creating sufiicient liquid jaolaims. (01.183-25) low a predetermined level,

pressure within the apparatus to supply the circulating pumps withliquid at a pressure above that of the surrounding atmosphere.

Applicants with a knowledge of these problems of the prior art have foran object of their invention the provision of a liquid cooling systemfor electric process equipment which will remove objectionable gasesfrom the-liquid to maintain the high electrical resistance thereof.

Applicants haveas another object of their invention the provision of adeaerating system where both the storage reservoir and the deaeratingchamber are maintained under vacuum to prevent the cooling liquid fromreabsorbing gases from or in the'air. a a

Applicants have as another object of their invention the provision of'asystem employing a contact vacuum deaerator located at an elevationabovethe' pumping arrangement for circulating liquid through the systemin order to'build up a pressurev therein to 'overcome the action of thevacuum inthe deaerating chamber, thus avoiding the possibilityof leakageof air through nuinerous system connections.

, Applicants have as a further object of their invention the provisionof a system with a deaerator'havingthe storage tank and deaeratorchamber in a single vessel and in communication with each othertofacilitate evacuation and removal of undesirable gases. I

Applicants have as a further object of their invention th provision of asystem with a deaerator having a storage tank which automatically feedsliquid to the system when the height of liquid in the deaerator sectionfalls below a predetermined level. i

Applicants have as a still further object of their invention theprovision of a liquid circulating system for deaeration'of liquids withpressure control inthe return line feeding the deaerator to maintainconstant circulation of liquid in the process piping, in the event thevacuum falls be- Other objects and advantages of our invention willappear irom the following specification and accompanyingfdrawing and thenovel features thereof:will beparticularly pointed out in theannexedclaims, f

In the'drawing, the sole figure is a schematic diagram ,oifjour improvedsystem showing the deaerator in sectio'rn, w

Referringto the drawing in detail, I designates a contact type vacuumdeaerator in the form of an upright cylindrical tank divided into anupper deaerating chamber 5 having'an-active liquid under vacuum.Positioned at a level below the deaerator is a circulating pump 2 whichis: connected to the lower part of chamber below the usual liquid levelthereof, by a line I4. The pump 2 is then connected by line l6, throughthe process cubicles I! to the coolers. [8. They discharge cooled liquidthroughline [9 into the upper end of the deaerator tank I and chamber 5through the end of pipe I0 into a tray or trough 23 which continuallyoverflows so that liquid therefrom passes down through a honeycomb orlattice work or over a set of overlapping baflles such as 2|. The liquidcascades over the surfaces of the bafiies or slats and gives off oxygen,carbon dioxide and other gases absorbed therein.

Vacuum is created'in connecting chambers 5 and 3 through line 22, whichmay be connected to conventional vacuum equipment, preferably a steamejector 23 supplied with steam from line 24 which discharges liquidthrough line 40 to reservoir 3. The lower extremity of reservoir 3 feedsinto line l6 through line 26 containing pressure valve 9 controlled fromline 21 which leads to chamber 5 so that when the water level in thechamber falls below a predetermined point 8, the operation of the floatvalve 4| through a lever or pressure medium opens valve 9 permittingwater to flow from storage reservoir 3 through line 26 and valve 9 intoline I4 and. into the system.

In'the operation of the system pump 2 operates under pressures at orslightly above atmospheric in line M'due to the static head of liquid inline 14 being in excess of the vacuum in chamber 5 created by the steamvacuum system 23. In order to overcome the effect of the steam vacuumsystemon the flow of liquid in line H and to aid the pump 2 in itsoperation, tank I is preferably placed at some elevation above pump 2 inorder to build up a pressure at the inlet of pump 2.

Liquid flowing through line M and pump 2 feeds into the process cubiclesI! through line U l6, thence through closed coolers 13 in order to lowerits temperature and dissipate the heat absorbed from the processcubicles ll. While the coolers l8 may be of usual design, they arepreferably of a type which do not expose the liquid to the atmospherewhere it might absorb air or undesirable gases. Any type of heattransfer unit where the heat is transferred to a secondary coolingliquid which passes over tubes through'which the primary cooling liquidpasses, is preferable. The secondary liquid may be cooled by a coolingtower, which causes evaporation, or by spraying or otherwise as may seenmost practicable.

On leaving the coolers IS, the cooled liquid is returned throughline l9to the upper end of tank I. Connecting line M with line I9 is line 29containing pressure valve ll controlled from line 28 which is in turnjoined to line Hi. In the event of a decrease in vacuum in the deaeratora higher, pressure will be created in line 28 which is communicatedto-valve H causing it to open and permitting recirculation of liquid topump 2, thus insuring the supply of cooling water to process.

Where the tank I is at a considerable elevation above pump 2, such pumpmay not develop sufficient pressure to return the liquid to the top oftank Iin case vacuum is lost in the deaerator. The resulting increase inpressure created in line 28 will open valve ll thus reliev ing thepressure on pump 2 and maintaining flow of cooling liquid to process, asdescribed in the foregoing.

To initially supply water to the system and replace water used or lostduring operations, a supply main 30 feeds into line I9. Flow of waterthrough. main 30 to line I9 is controlled by pressurevalve 3| throughfloat operated valve 32 for controlling the pressure applied throughline 33 to valve 3|. Float valve 32 is connected to storage reservoir 3through lines 34, 35 and is responsive to water level in that reservoirfor controlling the operation of valve 3|. On the other hand, water maybe removed from the system through line 36 and three-way valve 31. Theline 24 mayxalso be drained into the reservoir 3 through line 42 byopening valve 43.

Having thus described our invention, we claim:

1. A deaerating system of the character described comprising acontainer, a diaphragm positioned across said container dividing it intoan upper and a lower chamber, a bafile arrangement positionedintermediate of said upper chamber for the passage of liquid to removeentrained gases, means for removing liquid from one extremity of saidupper chamber for circulation through a system including heat exchangeunits and for returning the liquid to the other extremity of thechamber, said lower chamber serving as a liquid storage reservoir, meansfor connecting said reservoir into the circulating system,rmeansresponsive to liquid level in said upper chamber for regulating the flowof liquid from the reservoir to the system, and means for placing theupper and the lower chamber under vacuum pressure. 7

2. A deaerating system of the character described comprising acontainer, a partition for dividing the container into an upper and alower chamber, a circulating system including heat exchange unitsconnected to the extremities of said upper'chamber, a baffle arrangementpositioned in an intermediate. portion of the upper chamber, means forcirculating liquid from the lower extremity of the upper chamber throughthe circulating system to vthe upper extremity of the chamber wherebythe returning liquid flows downwardly by gravity over the bafiiearrangement to release entrained gases therefrom, means for connectingsaid lower chamber to said circulating system for removing liquidtherefrom, means responsive to the liquid level in the upper chamberforregulating the flow of liquid from the lower chamber to thecirculating system, and means for placing the upper chamber and thelower chamber under a vacuum pressure. p

3, A. deaerating system of the character described comprisingacontainer, a partition for dividing the container into a deaeratingchamber and a liquid storage chamber, means for circulating liquidthrough a system including a plurality of heat exchange units andthrough the deaerating chamber, means carried by the partition forcommunication between the deaerating chamber and the storage chamber,whereby liquid reaching a predetermined level in the deaerating chamberwill drain into the storage chamber, and means responsive to the liquidREFERENCES CITED level in the deaerating chamber for connecting Thefollowing references are of record in the the storage chamber with thecirculating sysfile of this patent; tem for supplying liquid thereto.

4. A deaerating system of the character de- 5 UNITED STATES PATENTSscribed comprising a container, a partition for Number Name Datedividing the container into an upper deaerating 1,611,256 Suczek Dec.21, 1926 chamber and a lower liquid storage chamber, 1,636,361 GibsonJuly 19, 192 an overflow pipe extending upwardly from the FOREIGNPATENTS partition into the deaerating chamber whereby 10 liquid reachinga predetermined levelxin the de- Number fi Date aerating chamber willoverflow into the storage 1711757 Great 17) 1921 196,064 Great BritamApr. 12,1923

chamber, means for circulating liquid through a system including a heatexchange unit and through said deaerating chamber to release en-- 15trained gases therefrom, and means responsive to the liquid level in thedeaerating chamber for connecting the storage chamber with thecirculating system to supply liquid thereto.

ALTON KIRIQATRICK. 20 HARRY H. MclVlIElEiN.

